Thin-film-transistor driving liquid crystal displays (TFT-LCDs) are widely used in the note book computer and portable TV. There is a tend that the application of TFT-LCD is expanding to desk computer and large area TV. Liquid Crystal displays have advantages of low power consumption, low weight and reasonable good optical performance. However, its viewing angle is much worse than CRT, especially in the vertical viewing zone. To solve the viewing angle problem of liquid crystal display, many muti-domain methods were proposed. Among them are mask rubbing two-domain method.sup.11, fringe field two-domain method.sup.12, double alignment layer two-domain method.sup.13 and UV treatment two-domain method.sup.14. These methods are either too complicated in process or they may cause other problems, such as image sticking. In this invention, new muti-domain methods based on the ion beam alignment technology are described.
Aligned liquid crystals are widely used in flat panel display technology. They are aligned by inducing anisotropy on the surface of a substrate. This surface is usually a polymer such as polyimide, coated on a glass substrate.sup.1. There are a number of ways of introducing anisotropy on the surface: rubbing.sup.2, stretching a polymer.sup.3, a Langmuir-Boldgett film.sup.4, a grating structure produced by microlithography.sup.5, oblique angle deposition of SiO.sub.x.sup.6, and polarized UV radiation of polymer films.sup.7. The pervasive method used in aligning liquid crystal displays available on the market today is rubbing a polyimide film with a velvet cloth. This method has some drawbacks.sup.8. These include the debris left by the cloth during the rubbing process in an otherwise clean room environment; concern with electrostatic discharging and its influence on the electronic circuitry below the thin polyimide film; and rubbing, being a macroscopic process, does not readily lend itself to aligning liquid crystals in different directions at the spatial size of a pixel, which is usually of the order of a hundred micrometers. This local alignment is desirable to obtain a multidomain structure, which significantly increases the angle of viewing of the display. The limited angle of viewing of current liquid crystal displays is one of the limitations of this technology. We describe a new non-contact method of aligning liquid crystals. This method circumvents the problems posed by the rubbing technique.